PURPOSE: The cause of subacute necrotizing lymphadenitis, a rare disease in children, has not been completely clarified. This study was aimed to investigate the disease mechanism by examining clinical, radiologic, and immunohistochemical findings in children diagnosed with subacute necrotizing lymphadenitis after an excisional biopsy. METHODS: We examined 19 lymph node tissue specimens from 17 children diagnosed with subacute necrotizing lymphadenitis at Gyeongsang National University Hospital from March, 1998 to July, 2006. A retrospective survey of the medical records was performed. CT findings were analyzed. Immunohistochemical staining was done on tissues obtained by excisional biopsy from all patients. RESULTS: The patient's age ranged from 5 to 19 years (average age :11.8 years). The main symptoms included a neck mass (17/19), pain in the mass (6/17), and fever (12/19). The palpable lymph nodes were mostly cervical in location; the maximum diameter, which was measured radiologically, was less than 3 cm in all 10 cases. The masses were pathologically divided into proliferative, necrotic, and xanthomatous types. With immunohistochemical staining the masses were divided into lesion (L), perilesion (PL), and necrosis (N). The CD8 staining was stronger than the CD4 staining for all regions in three types. The CD4 staining intensity was mainly increased in the perilesion, and CD8 was mainly increased in the lesion. CONCLUSION: We compared the radiologic findings, clinical symptoms, and pathology to help understand the cause of disease in patients with subacute necrotizing lymphadenitis.